The Research On The Short-circuit-ring's Welding Of Motor

Copper alloy with high conductivity and high strength is widely used for wind mill generator and pulling motor used for electric express locomotive to reach to high power and small in size. The welding of end ring of alternating current machine and the conducting bar is the key technology for manufacturing of asynchronous traction motor with high power. China South Locomotive and Rolling Stock Industry Corporation had taken this significative study as a key project for the manufacturing of alternating current machine. According to the welding of end ring of alternating current machine, the welding of copper and copper alloy is described in this paper. Results obtained in this study are as follows.1.By the comparison of oxyacetylene gas brazing, induction brazing and resistance brazing, it was found that high-quality welding joint could be obtained by induction brazing, which also had the highest efficiency.2.The welding of end ring of the high power synchronous traction motor once and for all using medium—frequency induction brazing ,which showed a variety of advantages, such as short circle, low heat affecting of conducting bar and end ring, without influence for rotor sheet insulation and with high mechanical strength and high quality.The design of an induction coil was the key point during integral welding of end ring in order to get high quality.3.By the investigation, induction coils with different dimension were designed for large-scale electric machine using multi-symmetrical induction brazing, which solved the problem of a tractor serves several purposes.4.Appropriate welding material, election of soldering acid, design of welding heat process and cleaning up influenced the welding quality significantly.More than one hundred motor rotors have been welded using integral induction brazing of end ring, which just have been used successfully for the areas of wind power generation, civil using and railway and so on. It follows that this welding processing is reliable and practicable, and it is suited for large-lot production.